1. Field of the Invention
The present invention relates to a method for controlling illumination light, and more specifically, to an electrical circuit and a control method remotely controlling LED brightness adjustment and color temperature adjustment.
2. Description of the Related Art
With the development of science and technology, the living quality of people is improved. Nowadays, a light control switch fixed to a wall no longer meets the demands for the use of people. Along with the widespread use of LEDs, the demands for light color temperature are increasing, and unchanged color temperature also fails to meet the demands for the living quality of people. In the related art, as shown in FIG. 1, resistors R12, R14, and R16, capacitors C12 and C13, a diode D2, an MOS tube Q6, an inductance L2, and a chip U7 constitute one constant current source (31) to drive a YLED1 having a yellow light 2700 K color temperature in a bicolor temperature LED light source (32). Resistors R13, R15, and R17, capacitors C14 and C15, a diode D3, an MOS tube Q7, an inductance L3, and a chip U8 constitute another constant current source (33) to drive a WLED1 having a white light 6500 K color temperature in the bicolor temperature LED light source (32). Signals received by a receiving module (29) are transmitted to a microprocessor (30). After the microprocessor (30) decodes the signals, two sets of light adjustment signals YPWM and WPWM are transmitted to the constant current source (31) and the constant current source (33) respectively to perform light adjustment and color temperature adjustment, so as to realize brightness adjustment and color temperature adjustment. However, this design method has the following two problems. First, a problem of maximizing a single color temperature output power. For example, when a fixed maximum output power of a lamp is 50 W, a yellow light YLED and a white light WLED both have a maximum output power of 25 W. Therefore, no matter how a duty ratio of the WPWM signal or the YPWM signal is adjusted, an output power of 50 W cannot be realized for a single color temperature. Second, when it is desired to adjust the brightness of a light without changing a color temperature thereof, both the color temperature and the brightness should be adjusted by controlling the two constant current sources due to the presence of the driving of the two constant current sources. Therefore, when the brightness (power) is changed, the color temperature also changes, making an operable range of the color temperature small. Thus, it is very difficult to realize the entire process.
In a time (nowadays) when the smart home application is very popular, it is apparently that the above product based on the above light control model is difficult to be widely spread or applied.